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Recruitment of the limpet Patella ulyssiponensis was investigated in relation to the presence of living crustose coralline algae (CCA) in rocky-shore habitats. Juvenile limpets (≤10 mm maximum shell length) were counted in CCA-present and CCA-absent habitats, on three shores in SW Portugal during summer 2007 and winter 2009. Furthermore, the settling response of laboratory-reared larvae of P. ulyssiponensis to CCA-covered substratum, and bare-rock, was examined. Across the intertidal zone, we found a clear association between the distribution and abundance of juveniles and the presence of CCA. Although the presence of CCA was not an absolute requisite for juvenile occurrence, null juvenile densities were mostly recorded in CCA-absent areas. The highest juvenile densities (maximum of 64 individuals in 15 × 15 cm) were consistently found in CCA-dominated habitats, namely steep wave-exposed areas at low-shore and rock-pools. The hypothesis of CCA-enhanced settlement was not supported, as settlement intensities of laboratory-reared larvae were similar between chips of rock encrusted by CCA and chips of bare-rock. From the overall number of settlers onto CCA-encrusted rock chips, 51% were found in tiny pits lacking CCA. This was the first study of the settlement patterns of larvae of the genus Patella using naturally occurring rocky substrata. These results are preliminary and should be confirmed with choice-experiments and improved monitoring of the position of settlers. We suggest that CCA plays a role in the recruitment of P. ulyssiponensis, potentially promoting survivorship of early benthic stages, but possibly not enhancing settlement.
The rocky shores of the north-east Atlantic have been long studied. Our focus is from Gibraltar to Norway plus the Azores and Iceland. Phylogeographic processes shape biogeographic patterns of biodiversity. Long-term and broadscale studies have shown the responses of biota to past climate fluctuations and more recent anthropogenic climate change. Inter- and intra-specific species interactions along sharp local environmental gradients shape distributions and community structure and hence ecosystem functioning. Shifts in domination by fucoids in shelter to barnacles/mussels in exposure are mediated by grazing by patellid limpets. Further south fucoids become increasingly rare, with species disappearing or restricted to estuarine refuges, caused by greater desiccation and grazing pressure. Mesoscale processes influence bottom-up nutrient forcing and larval supply, hence affecting species abundance and distribution, and can be proximate factors setting range edges (e.g., the English Channel, the Iberian Peninsula). Impacts of invasive non-native species are reviewed. Knowledge gaps such as the work on rockpools and host–parasite dynamics are also outlined.
Intertidal biofilms are a diverse mixture of bacteria, algae as well as sporelings of macroalgae embedded in a polysaccharid matrix. As the primary colonisers of newly formed surfaces, biofilms undergo a succession of different microbe assemblage until the mature state is reached. A biofilm can act as primary producers and as such recycle nutrients in a habitat. It will influence macrobiota by providing a food source or sending out cues to settlers. Biofilms themselves will be controlled by these settlers. This interaction between bottom-up and top-down plays a crucial part for the functioning of the rocky shore ecosystems. However, the diversity of biolfilms as well as it nature to react quickly to environmental changes makes identification and quantification of the individual compounds a difficult task. Subsequently, the understanding of biofilms in general and intertidal, rocky shore microbe assemblages has always tied to techniques and methods available at the time of study. This chapter focusses on the techniques that have greatly contributed to increasing knowledge of biofilms and discusses their findings. Nonetheless, newly developed methods promise to further this knowledge of the ecological role of biofilms on rocky coastlines.
Molecular characterization of pediatric low-grade glioma (pLGG) over the last decade has identified recurrent alterations, most commonly involving BRAF, and less frequently other pathways including MYB and MYBL1. Many of these molecular markers have been exploited clinically to aid in diagnosis and treatment decisions. However, their frequency and prognostic significance remain unknown. Further, a significant portion of cases do not have any of these alterations and what underlies these cases remains unknown. To address this we compiled a cohort of 562 patients diagnosed at SickKids from 1990-2017. We identified molecular alterations in 454 cases (81% of the cohort). The most frequent events were those involving BRAF; either as fusions (most commonly with KIAA1549 (30%)) or V600E mutations (17%) and NF-1 (22%). Less frequently, we identified recurrent FGFR1 fusions and mutations (3%), MYB/MYBL alterations (2%), H3F3AK27M (2%) or IDH1R132H (0.5%) mutations, as well as other novel rare events. Survival analysis revealed significantly better progression-free survival (PFS) and overall survival (OS) of KIAA1549-BRAF fused patients compared to BRAFV600E with 10-year OS 97.7% (95%, CI 95.5-100) and 83.9% (95%, CI 72.5-95.6), respectively. In addition to survival, molecular alterations predicted differences in response to conventional therapeutics; BRAF fused patients showed a 46% response-rate, versus only 14% in V600E patients. pLGGs harboring H3F3AK27M progressed early with median PFS of 11 months. In patients with MYB/MYBL1, FGFR1/FGFR2 alterations, we observed only one death (FGFR1N546K case). The work here represents the largest cohort of pLGGs with molecular profiling and their impact on the clinical behaviour of the disease.
For livestock production systems to play a positive role in global food security, the balance between their benefits and disbenefits to society must be appropriately managed. Based on the evidence provided by field-scale randomised controlled trials around the world, this debate has traditionally centred on the concept of economic-environmental trade-offs, of which existence is theoretically assured when resource allocation is perfect on the farm. Recent research conducted on commercial farms indicates, however, that the economic-environmental nexus is not nearly as straightforward in the real world, with environmental performances of enterprises often positively correlated with their economic profitability. Using high-resolution primary data from the North Wyke Farm Platform, an intensively instrumented farm-scale ruminant research facility located in southwest United Kingdom, this paper proposes a novel, information-driven approach to carry out comprehensive assessments of economic-environmental trade-offs inherent within pasture-based cattle and sheep production systems. The results of a data-mining exercise suggest that a potentially systematic interaction exists between ‘soil health’, ecological surroundings and livestock grazing, whereby a higher level of soil organic carbon (SOC) stock is associated with a better animal performance and less nutrient losses into watercourses, and a higher stocking density with greater botanical diversity and elevated SOC. We contend that a combination of farming system-wide trials and environmental instrumentation provides an ideal setting for enrolling scientifically sound and biologically informative metrics for agricultural sustainability, through which agricultural producers could obtain guidance to manage soils, water, pasture and livestock in an economically and environmentally acceptable manner. Priority areas for future farm-scale research to ensure long-term sustainability are also discussed.
Phased Array Feed (PAF) technology is the next major advancement in radio astronomy in terms of combining high sensitivity and large field of view. The Focal L-band Array for the Green Bank Telescope (FLAG) is one of the most sensitive PAFs developed so far. It consists of 19 dual-polarization elements mounted on a prime focus dewar resulting in seven beams on the sky. Its unprecedented system temperature of ~17 K will lead to a 3 fold increase in pulsar survey speeds as compared to contemporary single pixel feeds. Early science observations were conducted in a recently concluded commissioning phase of the FLAG where we clearly demonstrated its science capabilities. We observed a selection of normal and millisecond pulsars and detected giant pulses from PSR B1937+21.
The Center for Astrophysical Research in Antarctica conducts various educational outreach programs as part of its mission as a National Science Foundation Science and Technology Center. The method behind the outreach programs is one of forging partnerships between Center researchers and other educational organisations. The main program serves primary and secondary students in Chicago. The core of the program is called Space Explorers and is targeted at high school students. These students attend a summer residential institute at the University of Chicago’s Yerkes Observatory. The high school Space Explorers then extend the reach of the program during the academic year by teaching in primary schools using a portable planetarium. The Center also pursues many other outreach activities and is in the process of forming an Antarctic Education Alliance.
To cope with phosphorus (P) deficiency, plants adapt root morphology to enhance inorganic P (Pi) acquisition from soil by allocating more biomass to roots, but whether the responses can be modified across gradients of P supply is not fully understood. The present study examined changes in root-length density (RLD), root-hair density (RHD) and root-hair length (RHL) of wheat (Triticum aestivum L.) in two contrasting soils, the Rough and Barnfield soils. Wheat plants were grown for 3 weeks in thin-plate rhizotrons in two soils with additions of 0, 10, 25, 50, 100 and 200 mg P/kg soil. Contrary to published literature, as P additions increased it was observed that a concomitant increase in RHL (250 to 1054 µm in the Rough soil and 303–1075 µm in the Barnfield soil) and RHD (57 to 122/mm in the Rough soil and 56–120/mm in the Barnfield soil), while RLD generally decreased (2480–1130 cm/cm3 in the Rough soil and 1716–865 cm/cm3 in the Barnfield soil). The levels of added P that resulted in critical P concentrations in the soils enabling maximum shoot biomass production were 50 mg/kg P in the Rough soil and 100 mg/kg P in the Barnfield soil, and these additions influenced root morphological changes. Under severe P deficiency, P supply increased RHL and RHD, but RLD was decreased. Improvement in lateral root and root-hair responses in wheat at extreme P deficiency may be a worthy target for breeding more sustainable genotypes for future agroecosystems.
The new Core-XAS (X-ray absorption spectroscopy) beamline (B18) at Diamond aims to provide a reliable spectrometer for a broad scientific community. With this in mind, B18 has been built as a general-purpose beamline and offers to users a variety of sample environments and detection methods. Here we will present the first commissioning results and some of the capabilities of this versatile instrument.
The UK was one of few European countries to document a substantial wave of pandemic (H1N1) 2009 influenza in summer 2009. The First Few Hundred (FF100) project ran from April–June 2009 gathering information on early laboratory-confirmed cases across the UK. In total, 392 confirmed cases were followed up. Children were predominantly affected (median age 15 years, IQR 10–27). Symptoms were mild and similar to seasonal influenza, with the exception of diarrhoea, which was reported by 27%. Eleven per cent of all cases had an underlying medical condition, similar to the general population. The majority (92%) were treated with antiviral drugs with 12% reporting adverse effects, mainly nausea and other gastrointestinal complaints. Duration of illness was significantly shorter when antivirals were given within 48 h of onset (median 5 vs. 9 days, P=0·01). No patients died, although 14 were hospitalized, of whom three required mechanical ventilation. The FF100 identified key clinical and epidemiological characteristics of infection with this novel virus in near real-time.
The autosomal recessive gene, dysgenetic lens (dyl) in the mouse has been mapped on chromosome 4. Two- and three-point crosses involving b (brown) and Mup-1 (Major urinary protein-1) indicate the following gene order: dyl–b–Mup-1. The approximate distance between dyl and b is 12 and between dyl and Mup-1 is 20 cM.
The study assessed conduct and emotional difficulties in a group of Romanian adoptees at age 11, and serves as a follow-up to assessments made when the children were 6 years old. It was found that there was a significant increase in emotional difficulties, but not conduct problems, for the Romanian sample since age 6. It was also found that emotional difficulty was significantly more prevalent at age 11 in the Romanian group than in a within-UK adoptee group. Emotional difficulties in the Romanian adoptee group were found to be significantly and strongly related to previous deprivation-specific problems (disinhibited attachment, cognitive impairment, inattention/overactivity and quasi-autism); however, the presence of such early problems did not account fully for the onset of later emotional problems. Five contrasting hypotheses concerning possible mediators for later onset of emotional difficulties for the Romanian group were examined. No links were found to duration of deprivation or other deprivation-related indices, stresses/difficulties in the postadoption family environment, or educational attainment and self-esteem. There was some evidence that emotion recognition might play a role in the emergence of these problems, but other measures of social competence and theory of mind showed no associations with the onset of emotional problems.
There is a growing need for optical fiber coatings that can sustain higher temperatures than present materials permit. To date, polyimides are used predominantly but they generally are difficult to process and usually require multiple depositions to achieve the desired film thickness. Perfluorocyclobutyl (PFCB) aryl ether polymers have demonstrated much success as processable and amorphous fluoropolymers, with particular emphasis on high performance optical applications. This work discusses recent efforts into perfluorocyclobutyl aryl ether polymer-based optical fiber coatings. A series of silica-based optical fibers were drawn with differing PFCB polymer coatings compositions and molecular weights on a Heathway draw tower. Results include a more than doubled usage temperature of coating (decomposition temperatures (Td) in nitrogen and air were above 450 °C) without affecting fiber mechanical properties and comparable isothermal stability to conventional coatings, except with a >150 °C higher temperature. Preliminary results of the first successful coating of optical fibers by PFCB polymers will be presented herein, as well as future endeavors.
We have found photometric indications that Interacting Eclipsing Binaries of early to mid F spectral type (and possibly A) have strong magnetic activity which would arise from convective atmospheres. Light curve solutions and periodicity studies revealing spots, magnetic breaking and magnetic cycles are presented in XZ CMi, V965 Cyg and V963 Cyg.
Sungo Bay (China) has a mean depth of 10 m, a total area of 140 km2 and is occupied by several types of aquaculture, whilst opening to the ocean. The production of scallops (Chlamys farreri) cultured on long lines is estimated to exceed 50 000 tonnes (total weight) per year. Selection of sites for scallop growth and determination of suitable rearing densities have become important issues. In this study, we focused on the local scale (e.g. 1000 m) where rearing density, food concentration and hydrodynamics interact. We have developed a depletion model coupling a detailed model of C. farreri feeding and growth and a one-dimensional horizontal transport equation. The model was applied to assess the effect of some environmental parameters (e.g. food availability, temperature, hydrodynamism) and spatial variability on growth, and to assess the effect of density according to a wide range of hydrodynamical and environmental conditions. In the simulations, food concentrations always enabled a substantial weight increase with a final weight above 1.5 g dry weight. Compared to a reference situation without depletion, a density of 50 ind m–3 decreased growth between 0% and 100%, depending on current velocity when maximum current velocity was below 20 cm s–1. The mean ratio between food available inside and outside the cultivated area (depletion factor) varied with the percentage of variation in scallop growth that was due to density. Our model suggests that scallop growth was correlated with maximum current velocity for a given density and current velocity below 20 cm s–1. The model was integrated within a Geographical Information System (GIS) to assist in making decisions related to appropriate scallop densities suitable for aquaculture at different locations throughout the bay. Concepts (depletion), methods (coupling hydrodynamics and growth models), and the underlying framework (GIS) are all generic, and can be applied to different sites and ecosystems where local interactions must be taken into account.